One of the highlights of my 40 plus years has been to see the resurgence of street performance. In the 70s and 80s, we believed we would never again see the heady days of street racing, street rods and tricked out loud cars with decals and tires ablaze. Boy were we wrong! This current wave of performance enthusiasm frankly makes the 60s look anemic by comparison. It is still good to remember our heritage.

One of the clear trends of this generation is to lower the car. Look at the popularity of this on the street and in the magazines. At NICO, questions to our online mechanics have been predominantly about performance tuning and the majority of those have been about lowering. Because of this, I thought it might be helpful to highlight a few aspects regarding the subject.

First, we should review the merits of going low…They include:

1. Lower center of gravity (CG) this reduces body roll when cornering and brake dive when braking. It will however, if nothing else is changed, decrease front to rear wheel weight transfer when accelerating hard off the line i.e. worse 60-foot times. 2. Cornering and lap times will usually improve. 3. It just plain looks cool, and it really looks cool with large diameter rims and wide, low profile tires

In order to get the benefits and avoid the draw-backs that I will mention later, you should consider the following:

1. Accurately determine how low you want to go. 2. Just lowering springs or lowering springs and matched shocks? 3. Coil- overs? 4. How stiff do you want your ride? 5. Do you mind a bouncy ride?

Let’s take each of these considerations and examine them individually.

How Low: This is really subjective. The decision points involve personal preference in terms of looks vs. performance. Lowering your CG is always a good thing from a cornering standpoint. But how low/what looks good is up to the individual owner.

Before making any final decisions you need to first determine just how low you can go before stuff starts dragging. To start with make sure your exhaust is properly hung and not low riding. Then put in the tire/rim combination that you will be using. Find the lowest point in the front and rear of the car and then get some eight-inch plywood cut into 6-inch squares and begin making stacks under these two points. Now you get some of your friends to come over to your place to have Pizza. After they have eaten a lot of Pizza you ask them to do you a favor and you take them to your car and ask them to bounce the front as hard as they can and then the rear. You watch and add plywood to the stacks until you get enough plywood that the car just begins to hit the plywood when bounced by your buddies. Measure your stack of plywood and subtract a half-inch from that number and that gives you an approximation of how low you can go except there is one more major variable and that is the clearance in your wheel well.

After you and your buddies have taken a break, you want to do the bounce test first with front and then the rear, looking at the wheel well to tire clearance with the wells straight, turned left to lock and turned right to lock. Your feeler gauge so to speak for this can be the same pieces of plywood duct taped to the highest aspect of the tire. Using the same math that I outlined before, you can calculate how much drop your wheel well will tolerate. The final variable would be the stiffness of the springs. A softer spring would give you less ability to drop as low and a stiffer spring would possibly allow you to drop lower. Because many lowering springs are progressive there is not a linearity that allows you to perform simple math to give you the magical number of how low can you go. You can however use percentages, e.g. if a spring is 20 percent stiffer you can guesstimate that you may be able to go 10-15 percent lower than calculated with the original springs. This is where coil-overs can be helpful because your choice of springs is greater.

The next question that we consider is the issue of shock/matched vs. unmatched lowering springs. In short, if you don’t buy a matched set you will have a ride that at times if not all the time will be bouncy. Aftermarket spring companies often try to match their springs to your factory spec shocks but this does not often pan out. It is really nice when you can purchase a matched set that provides adjustable shocks because then you can fine-tune your ride to meet your needs. This leads into the issue of coil-over springs.

Coil over systems are what we see on most modern purpose built racecars because their performance potential and tuning flexibility are so great. Coil over systems use a smaller diameter coil spring that sits mounted on a perch that can be adjusted up or down which in turn, raises the car up or down. This allows the owner to fine tune the ride height with a given spring rate. The other thing that many coil over systems allow you to fine tune are the spring rates themselves. That is if one spring is too soft you can replace it with a stiffer spring. The springs themselves are generally reasonably priced and they have ratings in terms of pounds as it relates to stiffness. This allows you to get dialed in rather quickly. If for example your 50-lb springs are too soft and you want roughly 20% stiffer, you can quickly calculate what pound spring you would want to change to.

To answer, how stiff do you want your ride you really have to do an inventory:

1. How much does performance matter vs. comfort? 2. Does body roll annoy you? 3. How much will you be driving the car? 4. How bumpy are the roads where you live? 5. Will there be a regular passenger and do you care what they think? If you care you may want to consider their preferences as well.

My last consideration which is do you mind a bouncy ride? This is somewhat rhetorical. I assume you don’t, when you bounce it gets annoying and worse, you look like a dork. So the real question is do you mind it enough to spend the money and the time necessary to minimize the bounce?

Remember that lowering your car and or putting on wider tires all necessitates a trip to a good four-wheel alignment shop to reset your camber, toe and in many cases castor as well. Neglecting to do this will result in poor of not dangerous handling and uneven and premature tire wear.

Finally, there are some possible drawbacks to lowering your ride:

1. You go too low and impact the ground causing damage to your car. 2. In some cases cv joints and bearings can wear out faster. 3. Decreased 60 foot times if other adjustments are not made 4. The bounce factor 5. Ride too stiff 6. Ride too soft

I hope this will be helpful in your quest to drop. If we can be of any further help please drop me a line. Best wishes and remember its not just who you know but it’s how low you can go.

Contributed by: Speeddoctor